What are the visa & residency requirements in San Sebastian?

"In order to visit San Sebastian, visitors must obtain a Schengen visa from the Spanish Embassy or Consulate in their home country. The process of applying for a visa involves submitting a completed application form, valid passport, two passport-sized photographs, proof of travel insurance, proof of sufficient funds, and a letter of invitation from a host in Spain. In order to obtain residency in San Sebastian, Spain, applicants must apply for a residence permit from the Spanish Embassy or Consulate in their home country. The process of applying for residency involves submitting a completed application form, valid passport, two passport-sized photographs, proof of sufficient funds, proof of health insurance, and a certificate of registration from the local police station," remarked another expat in San Sebastian, Spain.